Sustainable Garden Rooms
Built to Last, Built Right
Our 2026 eco-standard is not a premium upgrade — it is the baseline. Every garden room in our recommended installer network is built to these sustainability credentials as a minimum requirement.
0.18 W/m²K
Wall U-value
A++
Energy rating
95%
SIPs recyclable
FSC
All timber
£0
Concrete used
35yr
Design lifespan
Our Six Sustainability Commitments
These are quantifiable, verifiable standards — not marketing language. Every point below can be documented and evidenced for any completed build in our network.
Net +
Carbon from day one
Ground screw foundations displace no soil and require no concrete. Combined with FSC timber and our Just One Tree planting partnership, every build is carbon-positive within its first operating year.
95%
SIPs recyclability
The Structural Insulated Panels used in every 2026 build are 95% recyclable by weight. OSB facings and polyurethane foam cores can be separated and processed through established waste streams at end of life.
A++
Energy rating
A correctly specified 2026 garden office — 0.18 W/m²K walls, A-rated glazing, and an air-source heat pump — achieves an A++ energy rating. The same standard as a new-build house under current Part L requirements.
500W
Typical winter heating load
A 20m² garden office built to our 2026 thermal standard requires less than 500W of continuous heating input to maintain 21°C in a London winter. That is the same power draw as five old-style incandescent bulbs.
4t CO₂
Annual commute eliminated
For a full-time remote worker, eliminating a 60-minute-each-way London commute removes approximately 4 tonnes of transport carbon from their annual footprint. The garden room's own embodied carbon is recovered within the first year.
70%+
Recycled content (composite)
Where clients choose composite cladding over timber, we specify boards with a minimum 70% recycled polymer content — diverting waste plastic from landfill and providing a 25-year zero-maintenance finish.
Why We Use Ground Screws — Never Concrete
The foundation is the most consequential sustainability decision on any garden room build. A concrete pad involves excavation, cement production (one of the most carbon-intensive industrial processes on earth), spoil removal, and permanent soil sealing. It is irreversible.
Ground screws are helical steel piles driven into the ground by a mechanical driver. The process takes 2–4 hours. No excavation. No concrete. No spoil. The screws pass between root systems rather than severing them. The soil profile is undisturbed. If the building is ever removed — in 35 years, or 5 — the screws are extracted and the garden is restored.
In London's clay-heavy soils, ground screws also outperform concrete pads structurally — they are unaffected by the shrinkage and heave cycles that can cause concrete slabs to move over time.
Part L 2026: Our Thermal Standard in Numbers
The 2021 revision of Part L raised the thermal performance bar for new builds by 31%. Our 2026 baseline exceeds this revised standard by a further 31% on wall U-value — delivering a 0.18 W/m²K specification where the regulatory minimum is 0.26 W/m²K.
In practical terms, a 20m² garden office built to our specification uses approximately half the energy of a comparable build to the 2018 standard, and roughly one-eighth the energy of a 1990s-era insulated shed. Over a 35-year lifespan, the cumulative energy saving is approximately £8,000–£12,000 at current UK electricity tariffs.
When paired with solar panels — increasingly specified on garden office roofs in 2026 — a well-positioned build can achieve net-zero or net-positive energy consumption across the year.
Just One Tree — Our Carbon Partnership
Every garden room project completed through our network contributes to our partnership with Just One Tree, a non-profit reforestation initiative. One tree is planted for every project completed — offsetting residual embodied carbon from the manufacturing of materials and ensuring that each new garden room is carbon-positive from its first day of use.
Build to the 2026 Eco-Standard
Every installer in our network builds to these sustainability credentials. Get matched within 24 hours.